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<p>Centella (<em>Centella asiatica</em> L. Urban) originally is a wild plant that is being cultivated to be medicinal and cosmetics raw material. The process of centella cultivation is relatively easy and can be grown in a variety of altitudes. One obstacle in centella cultivation is weed growth. The proper handling of weeds in centella plantation requires data on the weed types and characteristics. This research aimed to determine the weed types and the amount of weed found in centella cultivation. Sampling was carried out purposively based on the presence of weeds in the cultivation area. Weed inventory was carried out using linear vegetation methods in 12 plantation beds of centella, with a size of 6 x 2 m² each. Observations were made during weeding on one cropping season. Weed inventory was carried out by recording the number of species and number of individual weed and taking documentation of weeds that were recorded for identification purposes. Research data were analyzed by using vegetation analysis. The weed vegetation analysis on centella plantations showed that there were 35 species of weeds identified from 20 plant families. <em>Cyperus rotundus</em> L. dominates the weed vegetation in centella plantations because of its high adaptability and its allelochemical exudates. To sustainably cultivate the centella, proper techniques of weed controls need to be applied by considering the nature of <em>Cyperus rotundus</em> L.</p>

<p>The increasing demand of jamu/traditional medicine was followed by the demands of raw materials quality based on Good Agricultural and Collection Practices (GACP) yield and standard quality. Bio-insecticide is an effort to fulfill the standard based on GACP. Indonesian’s biodiversity have many potential raw materials of bio-insecticides, such as <em>Tithonia diversifolia</em>. The most common pest in the medicinal plants is <em>Aleurodicus dugesii</em> (giant whiteflies), this insect belong to Hemiptera ordo and Aleyrodidae family. The research was conducted to determine the antifeedant and anti-oviposition activity of Tithonia bio-insecticide against giant whitefly on Coleus species. The experimental design was completely randomized design (CRD) with five treatments of Tithonia leaves extract consentrations. Those consentrations were 0, 4, 2, 1, and 0,5 mg L^-1. The treatments were tested by using a no-choice test with three replications. The extract of Tithonia leaves was prepared by infundation method by using water solvent. Results showed that extracts of Tithonia with the smallest concentration (0,5 mg L^-1) has an active role as an anti-oviposition and antifeedant on giant whiteflies.</p>

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Dunia berkembang kian cepat seiring majunya teknologi informasi. Komunikasi kini menjadi tidak terbatas. Dengan banyaknya kemudahan untuk melakukan pengaksesan informasi, adakalanya diperlukan pengamanan informasi tersebut. Pengamanan ini berfungsi menangani pencegahan atas sampainya informasi ke tangan yang tidak berhak yang dapat menimbulkan kerugian bagi pemilik informasi. Metode Playfair Cipher merupakan salah satu metode yang digolongkan dalam kriptografi klasik yang proses enkripsinya menggunakan pemrosesan dalam bentuk blok-blok yang sangat besar. Metode Playfair Cipher menggunakan pembentukan tabel berdasarkan kunci yang diketahui. Penulis melakukan modifikasi metode Playfair Cipher menggunakan tabel 8x8 ini mempersulit pemecahan analisis digram dan frekuensi analisis karena semakin acak isi tabel akan menghasilkan ciphertext yang acak. Hasil pengujian ini yaitu pada aplikasi ini memberi dua layanan keamanan data saja yaitu Confidentiality dan Authentication, penggunaan kunci Metode Playfair Cipher jika penggunaan kunci yang digunakan panjangnya lebih pendek maka semakin cepat juga waktu enkripsi dan dekripsinya dan terdapat karakter tambahan yaitu karakter Space